During the rapid laser pulse heating and consecutive cooling in laser-induced incandescence (LII), soot particles may undergo thermal annealing and sublimation processes which lead to a permanent change in its optical properties and its primary particle size, respectively. Overall, effects of these two processes on soot and LII model-based particle sizing are investigated by measuring the two-color time-resolved (2C-TiRe) LII signal decay from in-flame soot after two consecutive laser pulses at 1064-nm wavelength. Experiments are carried out on a non-premixed laminar ethylene/air flame from a Santoro burner with both low and moderate laser fluences suitable for particle sizing. The probe volume is set to a radial position close to the flame axis where the soot particles are known to be immature or less graphitic. With the first pulse, soot is pre-heated, and the LII signal after the consecutive second pulse is used for analysis. The two-color incandescence emission technique is used for the pyrometric determination of the LII-heated peak soot temperature at the second pulse. A new LII simulation tool is developed which accounts for particle heating via absorption and annealing, and cooling via sublimation, conduction, and radiation with various existing sub-models from the literature. The same approach of using two laser pulses is implemented in the simulations. Measurements indicate that thermal annealing and associated absorption enhancement becomes important at laser fluences above 0.17 J/cm2 for the immature in-flame soot. After a heating pulse at 0.33 J/cm2, the increase of the soot absorption function is calculated as 35% using the temperature measured at the second pulse and an absorption model based on the Rayleigh approximation. Present annealing model, on the other hand, predicts graphitization of soot even in the absence of laser heating at typical flame temperatures. Recorded experimental LII signal decays and LII-heated peak soot temperature information are used for particle sizing with the LII modeling to assess the effects of sublimation. A reduction in particle size due to sublimation starts at a laser fluence of 0.1 J/cm2 for the in-flame soot. After a heating pulse at 0.33 J/cm2, the particle loses 55% of its initial mass.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
L.A. Melton, Appl. Opt. 23, 2201–2208 (1984)
C. Schulz, B.F. Kock, M. Hofmann, H.A. Michelsen, S. Will, B. Bougie, R. Suntz, G.J. Smallwood, Appl. Phys. B 83, 333–354 (2006)
R.L. Vander Wal, M.Y. Choi, K.O. Lee, Combust. Flame 102, 200–204 (1995)
R.L. Vander Wal, K.A. Jensen, Appl. Opt. 37, 1607–1616 (1998)
R.L. Vander Wal, M.Y. Choi, Carbon 37, 231–239 (1999)
S. De Iuliis, F. Cignoli, S. Maffi, G. Zizak, Appl. Phys. B 104, 321–330 (2011)
H.A. Michelsen, A.V. Tivanski, M.K. Gilles, L.H. van Poppel, M.A. Dansson, P.R. Buseck, Appl. Opt. 46, 959–977 (2007)
R.P. Bambha, M.A. Dansson, P.E. Schrader, H.A. Michelsen, Appl. Phys. B 112, 343–358 (2013)
R.L. Vander Wal, T.M. Ticich, A.B. Stephens, Appl. Phys. B 67, 115–123 (1998)
M. Saffaripour, K.-P. Geigle, D.R. Snelling, G.J. Smallwood, K.A. Thomson, Appl. Phys. B 119, 621–642 (2015)
H.A. Michelsen, J. Chem. Phys. 118, 7012–7045 (2003)
X. López-Yglesias, P.E. Schrader, H.A. Michelsen, J. Aerosol. Sci. 75, 43–64 (2014)
R.J. Santoro, H.G. Semerjian, R.A. Dobbins, Combust. Flame 51, 203–218 (1983)
E. Cenker, G. Bruneaux, T. Dreier, C. Schulz, Appl. Phys. B 118, 169–183 (2015)
R.J. Santoro, T.T. Yeh, J.J. Horvath, H.G. Semerjian, Combust. Sci. Technol. 53, 89–115 (1987)
F. Liu, D.R. Snelling, K.A. Thomson, G.J. Smallwood, Appl. Phys. B 96, 623–636 (2009)
E. Cenker, K. Kondo, G. Bruneaux, T. Dreier, T. Aizawa, C. Schulz, Appl. Phys. B 119, 765–776 (2015)
B.C. Connelly, Quantitative characterization of steady and time-varying, sooting, laminar diffusion flames using optical techniques (Doctoral dissertation), PhD thesis, Yale University (2009)
D.R. Snelling, F. Liu, G.J. Smallwood, Ö. L. Gülder, Combust. Flame 136, 180–190 (2004)
P.B. Kuhn, B. Ma, B.C. Connelly, M.D. Smooke, M.B Long, Proc. Combust. Inst. 33, 743–750 (2011)
H.A. Michelsen, F. Liu, B.F. Kock, H. Bladh, A. Boiarciuc, M. Charwath, T. Dreier, R. Hadef, M. Hofmann, J. Reimann et al., Appl. Phys. B 87, 503–521 (2007)
M. Hofmann, B.F. Kock, T. Dreier, H. Jander, C. Schulz, Appl. Phys. B 90, 629–639 (2007)
A.V. Filippov, D.E. Rosner, Int. J. Heat Mass Transf. 43, 127–138 (2000)
J.M. Mitrani, M.N. Shneider, B.C. Stratton, Y. Raitses, Appl. Phys. Lett. 108, 54101 (2016)
J. Johnsson, H. Bladh, N.-E. Olofsson, P.-E. Bengtsson, Appl. Phys. B 112, 321–332 (2013)
L.J. Dunne, P.F. Nolan, J. Munn, M. Terrones, T. Jones, P. Kathirgamanathan, J. Fernandez, A.D. Hudson, J. Phys. Condens. Matter 9, 10661–10673 (1997)
W.S. Bacsa, W.A. de Heer, D. Ugarte, A. Châtelain, Chem. Phys. Lett. 211, 346–352 (1993)
F. Liu, B.J. Stagg, D.R. Snelling, G.J. Smallwood, Int. J. Heat Mass Transf. 49, 777–788 (2006)
The research reported in this publication was supported by funding from King Abdullah University of Science and Technology (KAUST).
About this article
Cite this article
Cenker, E., Roberts, W.L. Quantitative effects of rapid heating on soot-particle sizing through analysis of two-pulse LII. Appl. Phys. B 123, 74 (2017). https://doi.org/10.1007/s00340-017-6653-7
- Pump Pulse
- Soot Particle
- Probe Pulse
- Flame Temperature
- Soot Volume Fraction